This invention is directed to radiation curable esters of polyfunctional hydroxyl-containing carboxylic acids for radiation curable compositions. The compositions are useful as coating compositions. They are particularly useful as radiation curable coating compositions over thin films of metal deposited on nonmetallic substrates.
It is known to apply a thin film of metal to a nonmetallic substrate to make a metallized substrate and to provide the metallized substrate with a protective coating. Such coated, metallized substrates are useful, for example, for articles such as containers and container caps for cosmetics. The substrates for such articles often are composed of heat sensitive materials such as heat sensitive plastics which can distort when exposed to elevated temperatures. It would be desirable to provide coatings for such metallized substrates that can be cured efficiently at temperatures below the temperatures at which such heat sensitive substrates distort. Moreover, it would be desirable to provide coatings for such substrates which are not only decorative, but also are highly adherent to the metallized substrate, are mar resistant, and are resistant to degradation by various solvents including both organic solvents and water. These and other objects will become apparent to one skilled in the art from the disclosure contained herein.